Voltage
Operating voltage of the auto lamp.
In different types of equipment, the voltage of on-board networks is also different. Therefore,
car lamps for passenger cars are designed for a voltage of 12 V, and
car lamps for trucks(and other similar equipment, such as buses) are designed for 24 V. However, there are also more specific options:
—
12/24 V. Lamps with the possibility of use in both types of on-board networks - both passenger cars and trucks. This versatility is found mainly among LED models, as well as in some types of xenon (see “Type”): these types of lamps are equipped with control circuits that can automatically adjust to the on-board network voltage.
— 85 V. Value found in models with xenon operating principle (see “Type”). In this case, we mean the voltage supplied to the lamp from the ignition unit (see below); the ignition unit itself is connected to the on-board network and is usually designed for 12 V. Data on the operating voltage of the lamp itself may be needed if you need to select a separate ignition unit for it.
- 40 V. Another option for increased voltage in xenon lamps; the meaning is completely similar to the 85 V described above, but is much less common.
Lifespan B3
Guaranteed lamp life according to B3 standard. In fact, this is the longest time that the lamp can continuously work with a 97% guarantee (it is impossible to provide a 100% guarantee in principle). This parameter is measured as follows: a test batch of lamps is used until 3% of them fail, the resulting time is indicated in the characteristics.
Other things being equal, longer-lasting lamps naturally cost more, but longer service life compensates for this disadvantage. Separately, we note that you should not confuse the guaranteed service life with the manufacturer's warranty — the conditions and warranty period may be different even for lamps with the same B3.
Lifespan Tc
The maximum continuous lamp operation time. This indicator is quite approximate and the probability that the lamp will work during this period is approximately 1 in 3. This is due to the measurement technique: a control batch of lamps is used until 63.2% of them fail, the resulting time and indicated as "maximum service life". However, the Tc data compared to the B3 guaranteed life (see above) provides a good estimate of the overall lamp life and its ability to last beyond the guaranteed life.